Swab.



lantea Mar.26,1912.

c. M. HBBTBR. swAB.

APPLICATION FILED JAN. 2K8, 1910. 1,021,600.

F Gal-L WITAN ESS ES, w'fw CHARLESM. HEETER, BUTLER, PENNSYLVANIA.

SWAB.

Specification of Letters Patent.

Patented Mar. 26, 1912.

Application filed January 28, 1910. Serial No. 540,602.

To all 'whom it 'may concern:

Be it known that I, CHARLES M. HEETER, a resident of Butler, in thecounty of Butler and State of Pennsylvania, have invented certain newand useful Improvements in Swabs, of which the following is aspecification. F

Swabs as now constructed for lifting water or oil from oil, gas andother deep wells are constructed with a single onesection rubber sleevewhich wears rapidly and must vbe frequently renewed, the greatest wearbeing at and adjacent the lower end of the sleeve.

One purpose of this 'invention is to protect this part of the sleeve tosuch an extent as to materially reduce the wear; also to provide forreversing the sleeve and thereby practically double its period ofservice.

A further purpose of the invention is to increase the efficiency of thesleeve by forming its upper part of softer rubber than the lower part,as I have found that a rubber of this character packs much more effectively in the casing than one .of uniform resiliency throughout.Furthermore, the efficiency is ,increased by forming the sleeve Iinsections, two such sections being here shown, with the upper section ofsofter rubber than the lower section, and both preferably so arrangedthat each may be turned end for end as the lower ends become worn. Afurther characteristic of the invention is the provision of a yieldingtop abutment for the sleeve with a spring for opposing upward movementof the abutment and exerting such downward pressure as to aid materiallyin effectively spreading the rubber within the casing. While the use ofthis movable top abut-ment and spring are not necessarily confined to arubber softer at--its upper end than its lower end, nor to-a sleeveformed in sections, the same when used in connection with these featuresprovides a very efficient swab.

An object-ion to swabs as now constructed is that the upwardly openingcheck ivalve,

vwhich permits upward flow of water or oil asthe swab is lowered andcloses when the swab is lifted, is frequently raised from its seatduring the upwardmovement by gas under high pressure within the well,and

when thus raised and opened the fluid Hows back through the swab,thereby defeating the very purpose for which the swab is used. Thisobjection is overcome with the present invention by providing valvemeans of such construction that the greater the pressure from'beneaththe more tightly the valve is heldclosed. In the present embodiment, anupwardly closing valve is employed which is arranged in connection withthe swab operating stem insuch manner as to'openr during the downwardmovement and close duringthe upward movement, the whole weight` of theswab being in fact on the valve during such upward movement, and withthe arrangement such that any upward gas pressure will tend to increasethe seating pressure of the valve.

In the accompanying drawings, Figure 1 isa vertical sectionof a swabyconstructed in accordance with the invention, and Fig. 2 illustratesthe improved swab in double form and within a well. f

Referring to the drawings, A designates the tubular stem of the swabwhich provides an upward vpassage for-water, oil and gas as the .swab islowered into aA well. Arranged on stem A is the swab rubber B having thering-like bot-tom abutment .C adjustably secured to the threaded lowerportion of the stem and a disk-like -top abutment D movable on the stem,and with a stout spring E embracing the stem between abutment D and thestop-forming head F secured to the upper end of the stem, spring Eopposing upward movement of abutment D and exerting downward pressurethereon.

As before stated, a characteristic of the invent-ion is a swab rubberhaving its upper portion of softer rubber than its lower portion, asthereby a more effec-tive packing within the casing is secured,particularly when. used with a movable spring-held top abutment. In theembodiment here shown, the rubber sleeve is in two sections b and b',with the upper section b `of softer rubber than the lower section. Anabutment G may beloosely arranged on stem A intermediate the sleevesections. 1

The sleeve wears or cuts away more rapidly at and adjacent its lowerend, and I have found that when the sleeve is 1n sections, eachsection1s subject to this wear.

` ButI such wear is materially reduced by so rendering such movementcomparativelyI confining the lower end of the rubber as to retardspreading, and this I accomplish by cupping the upper faces of abutmentsC and (l, as indicated at H, with the extremities of the sleeve sectionscircumferentially notched or reduced, as at J, to enter the cups. And bynotching both ends of each sleeve section, the latter may be reversedand full wear obtained from each, practically double the service securedfrom the non-reversible rubber now commonly used.

With` the bottom abutment C adjustable, the rubber may be tightened upfrom time to time as it becomes worn and until no further efiiciency canbe secured by contracting it longitudinally. Spring' E coperates withthis function of the adjustable bottom abutment, with the result thatrthe rubber is at all times maintained in condi tion for effectivefitting or packing within the casing. At the same time, the springpermits the rubber to so yield in upward direction during the downwardmovement of the swab' as to prevent excessive friction,

easy and at the same time relieving the rubber of much wear` which suchfriction would cause.

It is a common practice in casing wells to use heavier casing for thelower portionof the well than for the' upper portion, the lighter casingbeing used for say a depth of from 2,000 to 2,500 feet and the heaviercasing the remainder of the depth. Both weights of casing are of thesame external diameter, but there is usually an eighth of an inchdifference in gage between the metals of the two weights, which makesthe lighter casing a quarter of an inch larger inside the diameter thanthe heavier casing.

With the swab rubber arranged between the two fixed abutments asheretofore and of a size to closely fit the lighter casing, the rubberis subjected to great strain and wear when forced into the smallerdiameter Yof the lower and heavier casing, and is frequently so torn andmutilated as to be absolutely useless. With the construction here shown,the rubber, while fitting the larger diameter, yields upwardly in suchmanner as to enter thesmaller casing without injury. The reverse actionoccurs when the swab emerges from the casing of smaller diameter, thesleeve spreading readily and filling the larger diameter, whereas in theformer construction after the rubber has once been forced into theeasing of smaller diameter 1t does not pack efficiently in the largerdiameter and unavoidable back-flow around the swab results.

As here embodied, a chambered head K is secured to the stop-forming headF with stem A open thereto. A passage L is formed through the thickupper end of head K, and the lower end of this passage is realued toform the valve seat L, with lateral ports or outlets M above the seat.The operating stem N, smaller than 'passage L, extends therethrough andat its lower end carries th'e beveled valve-forming head O which fitsseat L and closes head K when the-swab is lifted by means of theoperating connection P to which stem N is secured. As the swab islowered in the casing, stem N and its valve head are in loweredposition, as in dotted lines in Fig. 1, thereby providing a free outletthrough ports M for the fluid flowing upwardly through stem A, butimmediately closing such outlet when the movement is reversed, theposition then being as in full lines in Fig. l. With this constructionit is obvious that upward pressure of gas through the stem cannotdisplace the valve, as with the upwardly opening check valve nowcommonly used, but rather increases the pressure of valve O on its seat,so that such excessivc gas pressure cannot operate as herey tofore torelease the fluid being raised.

In wells of great depth, and where very large columns of fluid must beremoved, it may be desirable to provide a swab of double construction,as shown in Fig. 2, which is accomplished by using two swabs constructedas above described, omitting the chambered head and valve from the lowerswab, and substituting a coupling head F for head F which serves tounite the tubular stems of the two swabs. Obviously, a swab ofpractically double capacity is thereby secured, i, e., a swab havingsuch casingpacking efficiency as to sustain the enormous weight of alarge column of fiuid which might be too great to bc effectively held bya single swab. A further advantage ofn this double construction is thatthe column of fluid is effectively held when passing an offset formed bythe sleeve and wall packer, such as R, Fig. 2. Such a sleeve is usuallyabout three-fourths of an inch larger inside diameter than the casing,and it is clear that a considerable volume will flow back around theswab while the latter is passing through, particularly when the space oflarger diameter is longer than the swab. With the double' swab theywhole length is such that the upper swab will fully Ipass such anoffset before the lower swab fully enters the same, 4and no back flowcan result.

By the terms rubber sleeve and swab rubber I refer to the full length ofthe rubber element' irrespective of the sections in which the same is ormay -be formed, 'and the claims are to be read with this understanding.

I claim:

1. In a swab, the combination of a tubular stem, a sleeve ofcompressible rubber conlined on the stem and ycompressed longitudinallyby the weight of a column of fluid lifted thereby, the upper portion ofthe compressible rubber being softer than the lower portion.

2. In a swab, the combination of a tubular stem, a sleeve oflongitudinally compressible rubber confined on the stem, the sleevefully filling the space between the tubular stem and the well casing andcompressed longitudinally by the weight ofa column of Huid, the upperportion of the sleeve being of softer rubber than the lower portion.

3. In a swab, the combination of a tubular stem, a rubber sleeveconfined on the stem and arranged in sections one above the other, bothsections being longitudinally compressible under the weight of a columnof fluid with the upper section yielding to greater compression than thelower section.

4. In a swab, the combination of a tubular stem, a longitudinallycompressible rubber sleeve confined on the stem, the sleeve arranged insections one above and closely adjacent to the other, an abutmentmovable on the tubular stem for the upper end of the sleeve, and 'acoiled' spring encircling the tubular stem and normally exertingdownward pressure on said abutment. y

5. A swab rubber of uniform transverse thickness from vend to end withits upper portion softer than its lower portion..

6. A swab rubber having a passage therethrough for atubular stem and ofuniform cross-sectional area from end to end with its upper portion ofsofter rubber than its lower portion. l

7. A swab rubber formed in sections of uniform transverse thickness fromend to end with the upper portion softer than the lower portion.

8. In a swab, a tubular stem. a rubber sleeve fitting the stem and ofuniformcrosssectional area from end to end, an abutment on the stem forthe lower end of the rubber, an abutment movable on the stem for theupper end of the rubber, and acoiled spring encircling the tubular stemand exerting constant downward pressure on the upper abutment.

' 9. In a swab, la tubular stem, a lrubber sleeve thereon having itsupper portion formed of softer rubber than its lower portion, andabutments for the upper and lower ends of the sleeve.

vl0. In a swab, a tubular stem, aV rubber sleevethereon formed insections arranged one above the other with the upper section of softerrubber than the lower section, and

abutments' for the sleeve.

11. In a swab, a tubular stem, a rubber sleeve' thereon formed insections arranged one above the other with the upper section of softerrubber than the lower section, an abutment between the sections, andabutments for the upper and lower ends of the sleeve. y

1Q. In a swab, a tubular stem, a rubber sleeve thereon formed insections arranged one above the other, the upper section of softerrubber than the lower section, an abutment secured to the stem forthelower end of the sleeve, a movable abutment for the upper end of thesleeve, and a spring for opposing upward movement of the upper abutment;y

18. In a swab, a tubular stem, a rubber sleeve on the stem, an abutmentsecured to the stem for the lower end of the sleeve, a movable abutmentfor the upper end of the sleeve, a stop device secured tothe stem abovethe upper'abutment, and a spring coiled around the tubular stem betweenthe stop device and the upper abutment for opposing upward movement ofthe latter.

,14. A swab having a Huid passage 'therethrough, a chambered head at theupper end of the passage with an opening through the upper end of thehead, the head formexi with lateral outlets intersecting saidv openingabove the lower end of the latter, an operating stem extending into thehead, and a valveforming head at the lower end of the stem closing thetop opening when Alifting the swab.

l5. In a swab, the combination of a tubular stem, two swab rubbersarranged on the stem one above the other to formv an elongated swab forthe purposey described, an

abutment fixed to the stem for the lower end of the lower rubber,movable abutments for the upper ends of the rubbers, and a spring. foropposing upward'v movement 'ofsaid movable abutments.

16. In a swab, a tubular stem, a rubber sleeve on the stem formed insections one above the'other, means fixed to the stem and engaged by thelower end of therubber sleeve, and a coiled spring encircling thetubular stem and exerting constant downward pressure on the upper end ofthe sleeve. y

17. A swab having a fluid passage therethrough, a chambered head at theupper end of the passage with an opening through the upper end of thehead, the under side of the upper end of the head forming a valve seat,the chamber having lateral outlets above the valve seat, an operatingstem adapted to bear against the upper end of the chambered head andvclosing the opening therethrough when lowering the swab inl a well, avalve stem projecting downwardly from the operating stem and throughthe, top opening in the chagnbered head, and a valve-forming head at thelower end of the valve stem adapted to engage said valve exertscompressing pressure on the lower seat when the operating stem is liftedfor rubber. Y 10 elevating the swab. In testimony Whereoj:l I aix mysignature 18. In a swab, the combination of a tubuin presence of twoWitnesses.

g lar stein, and two longitudinally eornpres- CHARLES' M. HEETER.

sible swab rubbers arranged on the stem one Witnesses: above the otherand spaced apart, the space JAMES O. CAMPBELL, between the rubbersreeelving fluid which GRACE E. HARKLESS.

